• Energy Research

Abstract Despite a series of transport decarbonisation initiatives, transport carbon emissions have been growing in both absolute and relative terms since 1990, and this is contributing to climate change. This study scrutinises the decoupling experiences of transport carbon emissions in 16 selected countries, including both developed and developing countries, over a 29-year timeframe (1990–2018). Resting upon the concept of socio-ecological resilience, collaborative planning and policy-implementation gap, a new conceptual framework is proposed to understand transport decarbonisation policies. In doing so, data of transport carbon emissions and Real Gross National Income in Purchasing Power Parity (based 2017) are first analysed. Progress of decoupling is then categorized for each country in every five-year period (a total of 96 data points). We then select consecutive periods when a country moves towards absolute decoupling (i.e. improvement) or deviates from it (i.e. worsening) and identify relevant policy instruments implemented based on a nine-component strategic framework that addresses the policy-implementation gap. Results indicate that defining clear sectoral objectives in action plans and integrating a holistic policy package to reinforce sustainable transport is pivotal. While there are no magic bullets to achieve transport decarbonisation, the strategic framework can help enhance policy effectiveness by formulating context-specific strategies.

Abstract The concept of decoupling embraces both immaterialisation and dematerialisation, by referring to the general delinking of environmental harm from economic production. This paper extends the theoretical debate and methodology on decoupling in transport to cover environmental (e.g. carbon) and social (e.g. fatalities) issues as well as the economic dimensions (e.g. income growth and transport activities). The typology developed here details the concepts of absolute and relative decoupling in a strong and weak version. This typology is then applied to explore the potential and the reality of transport decoupling in 15 major countries over the period since 1990, when concerns over the global environment and social issues have become a central part of the sustainable development agenda, through the measurement of changes in all three of the elements of sustainable development (economic, environmental and social). Two key transport externalities, carbon dioxide emissions and traffic fatalities, are studied, as these represent examples of environmental and social costs associated with increased levels of mobility. These 15 key countries included both developed and developing countries, and they together account for the majority of the global economy, carbon emissions and a substantial proportion of transport fatalities. The results show that decarbonisation of the transport sector has proved more difficult to achieve in the 15 countries over the 22 years than the reduction in the levels of transport-related fatalities. Nevertheless, there is progress being made. Decoupling has taken place in both developed and developing countries, though the experiences vary in terms of timing (earlier vs more recent), consistency (stable vs variable), form (absolute vs relative) and magnitude (strong vs weak). Recoupling effects are limited. Transport has proved to be the most difficult sector to make more sustainable, as it is growing so fast and as it is necessary to support economies and lifestyles. Yet through combining measures of economic (e.g. income), environmental (e.g. carbon) and social (e.g. fatalities) wellbeing, it has been possible to identify positive trends in decoupling transport at the national level, as measured through relative decoupling. The much harder objective of an absolute decoupling is only just beginning to take place, but this must be seen as the primary objective in moving towards sustainability in the transport sector.

Abstract Background The processes of transport decarbonisation are complicated. In this paper, we adopt the Activity-Modal Share-Energy Intensity-Carbon Intensity of Fuel (ASIF) approach and propose a conceptual framework on the direct and indirect impact of COVID-19 on transport CO2 emissions. In the Chinese context, changes of carbon emissions associated with passenger and freight transport (including urban, rural, and inter-city transport) across different transport modes are estimated. Scenario analysis is then used to estimate the impact of COVID-19 on total transport carbon emissions up to 2030. Four scenarios, from minimal to significant behavioural changes and global recession associated with COVID-19, are generated. Results Under the pandemic, the transport system in China was estimated to have produced 28% less CO2 emissions (1044.2 Mt) in 2020, when compared to 2019. Compared with the business-as-usual scenario, the estimated total transport carbon emissions in 2030 would drop by 6%, 15%, and 21% and 23% under the minimal-impact, low-impact, moderate-impact, and severe-impact scenarios, respectively. Conclusions The results suggest that the processes triggered by COVID-19 alone will not be sufficient to meet the ambitious transport decarbonisation targets. To meet China’s pledge under the United Nations Framework on Climate Change, the medium-term effects of COVID-19 must be combined with strong transport decarbonisation measures of modal shift and new energy applications. With these additional measures, it may be possible to advance the transport carbon peak before 2030. Lessons are relevant to other developing countries.

Addressing fatalities on road is a major concern in most countries in the world. South-East Asian countries are no exception. In Indonesia, three persons die on road every hour. Understanding where and how road traffic crashes happen is imperative before the most efficient countermeasures can be devised and implemented. In this paper, three tools—hot spots, hot zones and hot clusters—are used to identify sections of two main highways in the Province of Aceh that require most urgent action. Many countermeasures have been developed to address the problem of black sites (hot spots). Examples of implementation often come from Australia, Europe or North America. Less research exists on countermeasures in hot zones, even less so in the Global South (less developed countries from Southeast Asia, Africa and Latin America). This research applies quantitative spatial analysis that builds on existing works using the hot zone methodology and goes a step further by suggesting relevant countermeasures. More precisely, by taking into consideration the global urban-rural divide, this paper attempts to identify the most dangerous highway sections, in Indonesia, and to suggest appropriate hot zone countermeasures based on the characteristics of these hot zones. The results showed that urban highways, when compared to rural highways, were characterized by higher crash rates and a larger number of hot zones. Formulating hot zone countermeasures in urban environments should therefore consider their associated dangerousness and environmental features. Proposed countermeasures in urban roads include a stricter monitoring of the use of helmet, seat belt and cellphone, and the development of periodic communication and awareness campaigns.